Will you start-out on the lower difficulties with a high damage brainfart build or a safer build with more surv.?

Hard to say. I'll probably be trying out all the skills in the lower difficulties so I can decide which build I will go for after level 30. Currently I'm planning to play a WD heavily based on summons. But since there are so many skills I have never seen in action, I can't say for sure if I will like my build when I can finally test it.
If I'd knew how all the skills work, I'd go with a high damage build. Why waste time in normal/nightmare if all I want to do is get to hell anyway?

This build seems solid, it's very similar to what I have in mind. The only thing that is lacking is an ability that will give you back mana. Ofc you have the Spiritual Atunement passive, but I'm not sure if this is enough. Personally, I'd rather have an active abilty to refresh mana and pick Bad Medcine as a passive because it seems very useful to me.

1. Poison Dart (Golden Runestone)
Not much to say here, used it to fill up my mana.

2. Haunt (Alabaster Runestone)
A nice DOT, especially the 37% slow for 15 seconds is very useful in PvP. Slowed enemies are easier to escpape from, and easier to hunt down for your pets and teammates.

3. Spirit Walk (Alabaster Runestone)
Used to get away from enemies and heal self.

4. Zombie Dogs (Indigo Runestone)
Pets are always nice as a distraction. Indigo Runestone will increase your survivability alot, because the dogs will absorb 40% of your damage taken. So... either the enemy focuses the dogs and doesn't hurt you meanwhile, or he will focus you but will only deal reduced damage as long as the dogs live.

5. Gargantuan (Alabaster Runestone)
The gargantuan will damage and sometimes stun your enemies. Can also tank alot of damage. As I've never seen this skill in action, it might be that the Gargantuan is too slow for PvP and should be swapped for another skill.

6. Big Bad Voodoo (Crimson Runestone)
The ultimate support ability. 30% increased damage (20 seconds) for your allies is alot. This ability can be a match decider if used at the right time.

Passives:

Jungle Fortitude: 20% reduced damage for you and your pets is a must, because survival is the most important thing in PvP.

Zombie Handler: Your zombie dogs will receive a lot of damage, and since you want them to live as long as they could (because of the 40% damage reduction), 60% more life for them is essential.

Overall, I guess this build does offer a lot of survivabilty. Zombie Dog (40% reduced damage) + Jungle Fortitude (20%) + Bad medicine (30%) equals a total of 90% damage reduced. If you are still getting low on health, you can escape with Spirit Walk and will also get healed by doing this.
You can't deal any good damage, but that's not really your job with this build. You will slow the enemies with Haunt, stun them with you Gargantuan, reduce their dealt damage with Bad Medicine and improve your allies damage with Big Bad Voodoo.

I got a 120gb SSD some weeks ago. It was quite expensive, but it was a great investation. Not specifically for gaming, but for overall computer usage.

Windows boots in less then 10 seconds. Every program I launch is instantly ready.

While playing some games I noticed some more positive effects:
Battlefield 3: The time it takes to load between mapchanges is extremely shortened.
Heroes of Newearth: After the character selection, when the loading bars for all the players appear, I'm always first. Same for WC3.
WoW: Teleporting into instances or new zones is alot faster now.

These were just some examples I noticed.

I guess Diablo 3 could also profit from an SSD. I could imagine that load times between switching acts or any other place where data needs to be loaded from the hard drive could be greatly reduced. Ok, that's obvious.. but whatever. I really enjoy my SSD and would suggest to buy one if you got some spare money.